The present invention relates to a collection chute for use in an automatic weighing apparatus with a combinatorial weighing capability, and more particularly to a collection chute having two collection paths.
Automatic combinatorial weighing apparatus operate by supplying articles to be weighed to a plurality of weighing machines arranged in a circular pattern, effecting a combinatorial arithmetic operation on weights from the weighing machines, selecting a combination of weights which is equal or closest to a target weight, and discharging the articles from the weighing machines which give such a weight combination. For collecting the articles from the weighing machines selected by the combinatorial arithmetic operation and supplying them to a packaging apparatus or the like, the automatic weighing apparatus has a collection chute in the form of a hollow inverted conical body having a wide, open upper end disposed below weighing hoppers of the weighing machines.
The automatic weighing apparatus would have an increased processing ability per unit time by shortening intervals at which weighed articles are discharged. However, articles discharged in a prior weighing cycle and those in a next weighing cyle would tend to get close to each other while they slide down the chute, and eventually mixed together. Therefore, the articles would be difficult to be delivered to the packaging machine in separate quantities.
One solution to the above problem would be to provide a steeply inclined slide surface in the collection chute for causing articles to slide at a higher rate. This arrangement would necessarily result in an increased vertical dimension of the collection chute, and hence the weighing apparatus would be of an increased height.
There has been proposed a collection chute structure D, as shown in FIG. 1 of the accompanying drawings, composed of an inner chute E and an outer chute F. A plurality of weighing hoppers A are arranged in a circular pattern, and each of the weighing hoppers A has an inwardly openable gate B and an outwardly openable gate C. The inner chute E has an upper portion disposed in confronting relation to the gates B for receiving articles discharged from the gates B of the weighing hoppers A, and the outer chute F has an upper portion disposed in confronting relation to the gates C for receiving articles discharged from the gates C. The inner and outer chutes E, F have respective discharge ports E', F' for supplying articles to the packaging apparatus. By alternately or simultaneously opening the gates B, C of the weighing hoppers A, articles are separated into the inner and outer chutes E, F before they are supplied to the packaging apparatus. The above conventional collection chute arrangement is disclosed in U.S. Pat. No. 4,399,880.
As illustrated in FIG. 1, the angles of inclination of slide surfaces of the inner and outer chutes E, F and the lengths of the slide surfaces to the discharge ports are different from each other, resulting in different times required for the articles to slide down the inner and outer chutes E, F. Furthermore, there is a narrow gap G formed above a position where the slide surfaces of the inner and outer chutes E, F intersect. Any articles that happen to enter the gap G are caused to slide down at a reduced speed, and the weighing operation of the weighing apparatus has to be effected to meet the reduced slide rate of retarded articles. As a consequence, the weighing process is slowed.